Hiding JS code from old browsers

Question: How do I hide JS code from old browsers that do not support JavaScript?

Answer:
This question has become far less relevant now that virtually all browsers support JavaScript.
Nevertheless, to prevent old browsers from displaying your JS code,
you can do the following:

Immediately after the opening <script> tag,
put a one-line HTML-style comment without the closing characters,
so that the first two lines of your script would look like this:

<script type="text/javascript" language="JavaScript">
<!--

At the end of your script, put the following two lines:

//-->
</script>

Thus, your HTML file will contain the following fragment:

<script language="JavaScript">
<!--
Here you put your JS code.
Old browsers will treat it
as an HTML comment.
//-->
</script>

Old browsers will treat your JS code as one long HTML comment.
On the other hand, new JavaScript-aware browsers will
normally interpret JS code between the tags
<script>
and
</script>
(the first and last lines of your JS code will be treated
by the JavaScript interpreter as one-line comments).